Spinal Cord reading

spinal cord is surrounded and protected by cerebrospinal fluid, which is contained in the thecal sac formed by

spinal meninges

spinal meninges are _____ with the cranial meninges

continuous

what are the 3 layers of the spinal meninges

dura mater, arachnoid and pia

dura mater

tough outer layer that extends to approximately the level of S2

what is the thecal sac

extension of the dura mater

anterior thecal sac adheres

to the posterior longitudinal ligament and is separated from the vertebral column by an epidural space that contains fat and vessels

what separates the dura mater and vertebral column

epidural space

each spinal nerve is…

surrounded by dura mater

potential space is called

subdural space

subdural space runs between the

arachnoid and dura mater

arachnoid mater is connected to…

pia mater

The space between the arachnoid mater and pia mater is the

subarachnoid space

subarachnoid space

filled with cerebrospinal fluid and the blood vessels that supply the spinal cord

pia mater

highly vascular layer that closely adheres to the spinal cord

what happens to teh pia mater at L1

turns into filum terminale

lateral extensions of the pia mater leave the spinal cord to form pairs of

denticulate ligaments

denticulate ligaments attaches to…

dura, preventing lateral movement of the spinal cord within the thecal sac

The denticulate ligaments run between the

ventral and dorsal nerve roots within the spinal column

cone-shaped segment

conus medullaris

conus medullaris

most inferior portion of the spinal cord and is located at approximately the level of T12–L1.

cauda equina

horse’s tail and exits through the lumbosacral foramina

posterolateral sulcus

shallow depression on each side of the posterior median sulcus

white matter

(myelinated axons) comprises the external borders of the cord and is more abundant.

gray matter

nerve cells and runs the entire length of the cord. It is centrally located and surrounds the central canal

central canal

contains cerebrospinal fluid and is continuous with the ventricles of the brain

appearance of a butterfly

central canal

dorsal horns

contain neurons and sensory fibers that enter the cord from the body periphery via the dorsal roots at the posterolateral sulcus

afferent (sensory) nerve roots

dorsal horns

ventral horns

contain the nerve cell bodies of the efferent (motor) neurons.

efferent (motor) nerve roots exit the spinal cord via

ventral root

number of spinal nerves (pairs)

31

pairs that correspond to the cervical region

8

pairs that correspond to thoracic section

12

pairs that correspond to lumbar region

5

pairs that correspond to sacrum

5

pairs that correspond to coccyx

1

dermatome map

how spinal nerve provides a specific cutaneous distribution that can be demonstrated

arachnoid mater

thin transparent membrane that is attached to the inner surface of the dura mater.